Vocal Cord Stroboscope

1
Vocal Cord Stroboscope
Team MembersEric MillerStacey Hoebel
ClientsDoug MontequinDiane BlessDivision of
OtolarynologyUW Medical School
2
Overview

• Background
• Problem Statement
• Current Design
• Design Specifications
• Design Alternatives
• Final Design
• Future Work
• Questions?

3
Background

• Stroboscopes Endoscopes
• - Used to diagnose diseases and disorders in the
  vocal cords and larynx
• - Allows physicians to closely observe behavior
  and damage to the vocal cords

4

• How does the device work?
• Vocal cords vibrate 450 times per second
• Strobe light makes the rapidly vibrating vocal
  cords appear to slow down by periodically
  illuminating the area at a frequency close to
  that of the vibrations
• Principles of Talbots Law/ Sampling Frequency

5
Problem Statement
Design a strobe light to be used in conjunction
with an endoscope to observe damaged vocal cords.
The device must have a feature with which the
frequency of the strobe light can be manually
adjusted to as fine as 1/80 cycle. The design
must also be relatively quiet, small enough to
carry, and independent from a computer.
6
Current Design

• KAY machine model RLS 9100 Fiber optic cable
  runs from the light source, a large xenon strobe
  light in a metal box, to the endoscope. The
  device is attached to an computer, printer, and
  VCR.

7
Current Design

• Problems with Current Design - Excess noise
  interferes with simultaneous audio and
  video observation of vocal cords - Large and
  immobile - Dependent on a computer, which
  quickly becomes outdated - Manual frequency
  control dial inconveniently placed

8
Design Specifications

• Small (10 x 6 x 10)
• Quiet (lt10 dB)
• 50-600 Hz frequency
• Manually adjustable frequency (fine tuning 1/80
  cycle)
• Independent from a computer

9
Design Alternatives

• Basic Box
• Same strobe light used in KAY model RLS 9100
• Smaller, better insulated resonant box
• New circuit boards placed inside of box
• Manual frequency control device attached to
  endoscope
• Independent of a computer

10
Design Alternatives

• Satellite Design
• A reflective satellite shaped object is placed
  across from the light source to concentrate light
  at the fiber optic cable, which is adjacent to
  the bulb
• Manual frequency control device is attached to
  endoscope
• Independent of a computer

11
Final Design

• LED Design
• LED light source
• Foot pedal attached to light source provides
  manual frequency adjustment and fine tuning
• Carrying case for easy mobility

• Advantages of LED - Low Power - No IR - Long
  Life - Small

12
Final Design
13
Future Work

• Research specific LED components - Power
  consumption - Brightness (lumens) - Slew
  rates - Strobe capabilities
• Build a circuit for adjustable frequency
• Work on a digital display for frequency -
  Circuitry - Placement

14
Questions?